Extreme Heat – Resilience and Reach Code Opportunities

The threat of extreme heat in California continues to grow more frequent, intense, and dangerous for public health and safety. Though once considered a seasonal inconvenience, heatwaves are now emerging as a year-round public health crisis, with the number of extreme heat days expected to increase exponentially in many areas across the state, according to California’s Fourth Climate Change Assessment. As climate models predict even hotter and longer-lasting heat events in the coming decades, the urgency to adapt infrastructure and update local policy to protect public health has never been greater. Recognizing this need in 2024, the California State Legislature passed Assembly Bill 2684, which requires that extreme heat be included in updates to a jurisdiction’s General Plan Safety Element. One promising strategy that jurisdictions can include is the implementation of specific local reach codes that may help mitigate the effects of extreme heat.

AB 2684 Overview

California Assembly Bill 2684, signed into law on September 30, 2024, mandates that jurisdictions address the hazard of extreme heat in their General Plan Safety Element, starting on January 1, 2028. Alternatively, jurisdictions may incorporate existing documents like an Extreme Heat Action Plan into their Safety Element, provided that they summarize and integrate the relevant information. This requirement aligns extreme heat with other environmental hazards such as flooding, wildfire, and seismic risks, underscoring its significance in community planning.

This bill builds on existing law - namely the statewide requirement for jurisdictions to “prepare and periodically update a comprehensive, long-range general plan to guide future planning decisions” which includes seven mandatory elements: land use, circulation, housing, conservation, open-space, noise, and safety [Government Code (GOV) § 65302]. AB 2684 aims to enhance local resilience to extreme heat by ensuring that climate adaptation and hazard mitigation strategies are systematically included into long-term planning processes.

By recognizing the role of local jurisdictions in addressing heat-related risk, AB 2684 encourages cities and counties to adopt innovative building standards that go beyond state requirements. This creates a pathway for reach codes to be used more strategically – not only for decarbonization and energy efficiency, but also as a means to protect public health. Through measures like enhanced ventilation, passive cooling design, and the installation of efficient cooling systems, local reach codes can directly support the objectives of AB 2684, empowering communities to reduce heat exposure and build long-term resilience.

Reach Code Options

Reach codes can improve human health and safety by mitigating the effects of extreme heat through both appliance and envelope improvements as well as through innovative design strategies that reduce the effect of overall temperature increases on buildings. By requiring or incentivizing heat-resilient building practices, reach codes offer communities a proactive tool to protect residents from the worsening impacts of extreme heat.

For example, a jurisdiction could adopt a building performance standard (BPS) policy or a reach code for existing buildings that encourages heat pumps for space heating. Owners of buildings with gas heating equipment and no cooling (e.g., wall furnaces or central forced air furnaces) would then be encouraged to replace that equipment with a heat pump and gain space cooling along the way.

Cool roof reach codes are another option to mitigate extreme heat. Cool roofs, which reflect more sunlight and absorb less heat than standard roofing materials, can significantly lower indoor temperatures and reduce the urban heat island effect, providing critical relief during peak heat events.

Jurisdictions could pursue the FlexPath approach, which encourages owners undertaking remodels to improve thermal performance with measures such as better insulation, high-performance windows, or air-sealing. By choosing from a menu of efficiency options, owners can enhance the energy efficiency of their homes while maintaining comfortable indoor air environments without overreliance on mechanical cooling.

Another approach might be reach codes that encourage battery storage when the building has solar photovoltaics. The battery could be used to shift load out of the peak period of each day and especially during extreme heat events, thus lessening the accumulated strain on the grid.

Local Jurisdiction Actions

Los Angeles County has incorporated both infrastructure improvements and community engagement into their comprehensive strategy. Not only has the County adopted cool roof reach codes for the past several code cycles, but they have also begun developing a maximum temperature threshold for residential units to protect tenants from the effects of extreme heat.

The City of Los Angeles has also taken significant steps to incorporate heat resilience into its planning and operations through establishing the Climate Emergency Mobilization Office and appointing a Chief Heat Officer to spearhead efforts in combatting extreme heat. Inglewood, Long Beach, and Ventura County are also exploring policy options to mitigate the adverse health effects of rising temperatures in their regions.

Conclusion

Traditionally, local governments have struggled to access federal disaster mitigation funding for extreme heat because it was not specifically addressed in their hazard mitigation plans. Now, under the requirements of AB 2684 this obstacle is diminished, enabling communities to tap into essential federal funding for mitigation efforts. With this support, local jurisdictions can pair available funds with existing reach code strategies to better shield residents from the negative effects of extreme heat.